Materials such as carbon nanotubes and graphene are excellent materials for fast chemical sensing or bio-sensing due to their large surface-to-volume ratio and electronic sensitivity to surface molecules. See, for example, Balasubramanian et al., “Biosensors based on carbon nanotubes,” Anl. Bioanal. Chem., 385: 452-468 (March 2006).
However, the sensitivity of conventional sensors is limited by low-frequency 1/f noise. See, for example, Balandin, “Low-frequency 1/f noise in graphene devices,” Nature Nanotechnology 8, 549-555 (August 2013). Therefore, it would be desirable to be able to increase the signal-to-noise ratio to enhance detection sensitivity.
Further, in most applications data is collected from multiple sensors. The question then becomes how to extract data from the sensors in the most efficient manner. Techniques such as time-division multiplexing are often employed to reduce readout time. However, time-division multiplexing can only reduce readout to a certain limit. Therefore, it would be desirable to be able to speed up readout for high density sensor arrays.